Trace amine-associated receptor 1 is a stereoselective binding site for compounds in the amphetamine class

The demonstrated ability of amphetamine to functionally activate the rat trace amine associated receptor 1 (rTAAR1) and the subsequent reports of amphetamine activation of TAAR1 in rhesus monkey mouse, human, and human-rat chimeric TAAR1-expressing cell lines has led to speculation as to the role of this receptor in the central nervous system (CNS) responses associated with amphetamine and its analogs. The agonist potencies of ten pairs of enantiomeric amphetamines, including several with known CNS activity, at primate TAAR1 stably expressed in RD-HGA16 cells, robustly indicate the S-configuration to be associated with higher potency. Moreover, the rank order of potency to activate TAAR1 parallels the stimulant action reported by humans for the specific amphetamines. Taken together, these data suggest that TAAR1 is a stereoselective binding site for amphetamine and that activation of TAAR1 is involved in the modulation of the stimulant properties of amphetamine and its congeners. In addition, the observed parallel between hTAAR1 and rhTAAR1 responses supports the rhesus monkey as a highly translational model for developing novel TAAR1-directed compounds as therapeutics for amphetamine-related addictions.